Impurities removal from acidic solution of nickel cobalt complex hydroxide using pulsed disc and doughnut column

In this work, a 30 mm diameter pulsed disc and doughnut solvent extraction column was used for impurities removal from nickel cobalt complex hydroxide acid solution by solvent extraction. The effects of dispersed phase velocity, continuous phase velocity and pulse intensity on drop diameter, dispersed phase holdup and mass transfer were investigated. The results show that the drop size decreases gradually, and the dispersed phase holdup decreased initially and then increased with the increase of pulse intensity. The dispersed phase holdup increases with the increase of dispersed phase velocity but is independent of the continuous phase velocity. The experimental data of this study are predicted by correlations with regressed parameters. The average absolute relative error of drop size and dispersed phase holdup were 10.07 % and 18.28 %. With the increase of pulse intensity, the extraction efficiency of impurities decreased firstly and then increased. The number of mass transfer units and the height of mass transfer unit were calculated. The trend of number of mass transfer units of impurities are similar to extraction efficiency. Mass transfer results indicate that pulsed disc and doughnut column can be applied to the nickel cobalt complex hydroxide acid solution-P204/kerosene system.